It's the farthest any human-made object has ever travelled. And it's been a bumpy ride.

Scientists say seven microscopic particles collected by NASA's comet-chasing spacecraft, Stardust, appear to have originated outside our solar system. If confirmed, this would be the world's first sampling of contemporary interstellar dust.

From an exploding meteor over Russia to a giant serpent-like fish on the California coast, these stories made us say "Wow!" in 2013.